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iOS Swift Collections and Control Flow Control Flow With Conditional Statements Working With Logical Operators

Posted by Max Alax
Max Alax
Courses Plus Student 475 Points

How I can add if in loop?? Always a mistake! In what part of loop?

var results: [Int] = []

for n in 1...100 { if <#condition#> { <#code#> } } ERRORE?

2 Answers

Kyle Johnson
Kyle Johnson
33,528 Points
Kyle Johnson
Kyle Johnson
33,528 Points

You can always reference the Swift Programming Guide. I found this example there:

for index in 1...5 {
    print("\(index) times 5 is \(index * 5)")

    if (index % 2 == 0) {
        print("\(index) is even")
    }
}
// 1 times 5 is 5
// 2 times 5 is 10
// 3 times 5 is 15
// 4 times 5 is 20
// 5 times 5 is 25
// 2 is even
// 4 is even

WARNING! Solution below! For the challenge, this should help:

var results: [Int] = []

for n in 1...100 {
    // Enter your code below
    if (n % 2 != 0 && n % 7 == 0) {
      results.append(n)
    }
    // End code 
}
Max Alax
Max Alax
Courses Plus Student 475 Points

But I don't understand without !=0 and ==0 I see an error. For what are these values (!=0 and ==0) ?

Kyle Johnson
Kyle Johnson
33,528 Points
Kyle Johnson
Kyle Johnson
33,528 Points

!= means 'not equal' and == means 'equal'

Max Alax
Max Alax
Courses Plus Student 475 Points

I understand what they mean, I don't understand what for (!=0 and ==0) are in this situation if (n % 2 != 0 && n % 7 == 0)? We have for n in 1...100 = what for (!=0 and ==0) ???

Kyle Johnson
Kyle Johnson
33,528 Points
Kyle Johnson
Kyle Johnson
33,528 Points

This formula finds out if their is a remainder after dividing by 2: n % 2 != 0. If their is a remainder, n % 2 will not equal 0. This formula finds out if their is a remainder after dividing by 7: n % 7 == 0. If their is a remainder, n % 7 will not equal 0.

The for loop will iterate through all numbers starting at 1 going to 100. To find the odd number we want to divide the number by 2 and check to see if their is a remainder. If there is a remainder, we have an odd number. Same concept for finding numbers divisible by 7 only this time we want number that give us a remainder of 0.

Max Alax
Max Alax
Courses Plus Student 475 Points

Ok) thank you so much!

Max Alax
PLUS
Max Alax
Courses Plus Student 475 Points
Max Alax
Max Alax
Courses Plus Student 475 Points

Thank you :)